tollow



1964 F. s. TOLLOW FLUID HEATER CLEANER 6 Sheets-Sheet 1 Filed May 31.1962 '7 Inventor lllllllllllllllllllll 1". Q. L.

Horn 2 y:

Dec. 15, 1964 F. s. TOLLOW 3,160,907

FLUID HEATER CLEANER Filed May 51, 1962 6 Sheets-Sheet 2 Inventor z 9(-E; a, film/4) Alfor neys Dec. 15, 1964 F. s. TOLLOW 3,160,907

FLUID HEATER CLEANER Filed May 31, 1962 6 Sheets-Sheet 3 O R I I O Q IQ.

I l 1 Bl Q 9 Q 4 m:

I O Qv I E j I n a O E Q k 1 R R i l w 8 3 Inventor M 5% 5M1 AttorneysDec. 15, 1964 F. s. TOLLOW 3,

FLUID HEATER CLEANER Filed May 51, 1962 6 Sheets-Sheet 4 Inventor I W 5%w fi zm Dec. 15, 1964 F. s. TOLLOW FLUID HEATER CLEANER 6 Sheets-Sheet 5Filed May 31, 1962 F. S. TOLLOW FLUID HEATER CLEANER Dec. 15, 1954 6Sheets-Sheet 6 Filed May 31, 1962 Inventor United States Patent Ofilice3,160,907 Patented Dec. 15, 1964 3,166,907 FLUE HEATER CLEANER FrederickSidney Tollow, London, England, assignor to Babcock & Wilcox Limited,London, England, a British company Filed May 31, 1962, Ser. No. 199,119Claims priority, application Great Britain, June 2, 1%1, 2%,086/61 6Claims. (Cl. 15-317) I This invention relates to fluid heater cleanersof the -kind having an elongated lance or nozzle tube axiallyreciprocable to advance the nozzle tube from a retracted position and towithdraw the tube to the retracted position. Different forms of thiskind of cleaner are disclosed, for example, in the specifications of ourBritish Patents Nos. 636,052 and 769,593.

The output and size of tubulous vapour generating and vapour heatingunits used in power stations for the supply of electricity hasprogressively increased but, since the heat exchange surfaces must becleaned, the practical size of a unit is limited by the length of fluidheater cleaner nozzle tube available and difliculties arise in theprovision of satisfactory fluid heater cleaners having nozzle tubes ofthe lengths required in projected vapour generating and heating units.

When a long nozzle tube is advanced horizontally into a gas passcarrying gas at high temperature a substantial sag of the discharge endof the nozzle tube is inevitable. The strength of the nozzle tube metalis affected by the high temperature to which it is heated and to provideintermediate support is impractical. Substantial rigidity of the nozzletube by an increase in diameter cannot be obtained since such increaseis accompanied by a larger surface exposed to heat and for a given borethe weight of the tube is increased while an increase in born leads toless effective cooling by the cleaning fluid. By way of example, the sagto be expected at the discharge end of a nozzle tube having an externaldiameter of 4 inches and a length of 40 feet when fully advanced isappreciably greater than 1 foot.

A fluid heater cleaner is necessarily designed to effect the desiredcleaning when positioned a proper distance from the heat exchangesurfaces to be cleaned. In the case of a nozzle tube arranged to operatein the space between horizontal tube banks, if the fluid heater cleaneris positioned so that the discharge end when the nozzle tube has beenadvanced a short distance is ideally spaced from the two tube banks foreffective cleaning thereof the discharge end when the tube is fullyadvanced will be too far from the upper tube bank for effective cleaningof that bank. 7 Moreover, in order to avoid damage to the lower tubebank by cleaning fluid discharged at too close a range it may benecessary to increase the distance be tween the tube banks or decreasethe cleaning fluid pressure at the nozzle, thereby lessening theeffectiveness of the fluid heater cleaner throughout the travel of thenozzle tube.

tend to interfere with effective cleaning since the effective region ofcleaning changes in height with longitudinal movements of the nozzletube and the latter if near the bottom of the tube bank must-be soarranged that when fully advanced its discharge end is not too near thetube bends at the bottom of the bank.

In a fluid heater cleaner having an elongated lance or nozzle tubeaxially reciprocable to advance the nozzle tube from theretractedposition and to withdraw the tube to the retracted positionaccording to the present invention means are arranged automatically torock the nozzle Similarly, if a nozzle tube is arranged to penetratebetween the limbs of an upright bank of U-shaped tubes, the sagging ofthe discharge end of the nozzle tube will.

tube during its reciprocation in a manner tending to compensate saggingof the discharge end of the nozzle tube unler the force of gravityacting laterally on the said tu e.

The invention will now be described by way of example with reference tothe accompanying drawings, in which:

FIGURE 1 is a side elevation, mostly in section on the axis of thenozzle tube, of a long travel lance soot blower, the nozzle tube beingin retracted position;

FIGURE 2 is a plan of the soot blower;

FIGURE 3 is an outside elevation of the rearmost part of the sootblower; 1

FIGURE 4 is a plan of the. rearmost part of the soot blower in sectionon the line IVIV of FIGURE 3; I

FIGURE 5 is an end elevation of the soot blower frame, and

FIGURES 6 and 7 schematically show the sootblower with the nozzle tubein retracted and fully projected positions respectively. p

Referring to FIGURES 1 to 5 of the drawings, the soot blower illustratedis a long travel lance blower which in cludes a nozzle tube 1 of or ofabout 40 feet in length which may be advanced from the retractedposition in which it is shown through an aperture in a wall 2 of thecasing of a tubulous fluid heater with which the soot blower isassociated. The forward end 3 of the nozzle tube 1 is provided withapair of nozzle apertures 4 one diametrically opposite to the other andadapted to discharge steam for tube cleaning purposes at right angles tothe axis of the nozzle tube. While the nozzle tube is in the retractedposition the forward end 3 thereof is situated within a wall box 5 theinner end of which is open.

The nozzle tube 1 extends immediately outside the wall 2 through anozzle tubefront support 6 which is fixedly mounted on a frame or trackmember 7; the nozzle tube is also supported by a nozzle tube rearsupport 8 at the rear end 9 of the nozzle tube and extends through anozzle tube intermediate support 10 between the front and rear supports6 and 8. The rear and intermediate supports 8 and 10 are mounted on theframe 7 with the capability of movement along said frame in thedirection towards and away from the mentioned aperture in the wall 2.

The intermediate nozzle tube support 10 consists of a carriage 11 havingfour wheels 12, a casing 13 secured to the carriage and surroundingthenozzle tube, a spider carrying four rollers 15 of concave surfacescontacting the nozzle tube at equiangularly spaced locations therearoundand an inner member 21 which carries the spider and which is positionedwithin the casing 13 by ball bearings 22 which permit rotary movement ofthe inner member around the nozzle tube axis with respect to the casinglongitudinally of the frame 7 so that the support 10 may be movedtowards or away from the mentioned wall aperture.

The nozzle tube front support 6 diifers from the nozzle. tubeintermediate support 10 by the absence'of a wheeled carriage, but isotherwise of the same construction; the p casing 13 thereof is fixedlymounted on the frame].

The nozzle tube rear support 8 consists of a carriage.-

24 having four wheels 25 also fitting between-the flanges of thetrack-forming channel irons 23, a;casing'26.se-; cured to the carriage24, a ring 27 to which the nozzle tube rear end 9 is welded and. aninner member 28 which carries the ring at its front end and which ispositioned V support.

within the casing 26 by ball bearings 29 which permit rotary movement ofthe inner member 28 around an extension of the nozzle tube axis withrespect to the casing .26. The said inner member 28 carries at its rearend a gland 30 through which there extends a steam feed tube 31. a

The steam feed tube 31 is welded at its rear end .to a' support 32mounted on theframe -7 'at the rearend there- I to ensure that not toogreat a length of nozzle tube shall be unsupported outside the wall 2.

The lower end of the upright shaft 55 carries a sprocket 64 engaged by achain 65 also engaging a sprocket 66, which is arranged for driving,through an upright shaft 67, bevel'wheel 68 in a casing 69'secured'toone side of the frame 7. Within the casing 69 the bevel spur wheel 68meshes with a bevel wheel 70 formed integral with a nut 71 engaging athreaded part 72 of a shaft 73 which extends through the casing 69.Collars 74 and 75 within the casing 69 maintain the bevel Wheel 79 inengagement a carriage 34having four wheels 35 also fitting between theflanges of the track-forming channel irons 23 and mounting brackets41fora pair of rollers 42 of concave surfaces, one roller contacting the feedtube 31 from above and the other from below. V

The'steam feed tube 31 is adapted to. convey to the interior of thenozzle tube 1 for tube cleaning purposes steam of which the supply maybe controlled by operation of a steam valve 43 in an elbow piece 44secured to the feed tube rear support 32. Actuating means (not shown)are provided for automatically opening and closing the valve 43 duringoperation of the soot blower.

The power required for advancing and withdrawing the nozzle tube isprovided by a reversible electric motor 45 mounted on the frame 7 nearthe front end thereof; The motor 45 is arranged to drive a chainsprocket 46 at the upper end of an upright shaft 47 throughspeed-reducing with the bevel wheel 68, and a key 76 prevents rotationof the shaft 73.

The head 81 of the shaft 73 at the front end thereof is connected by alink 82 to theshor't arm 83 of a bell crank lever 84 secured to one endof cross shaft 85 in the frame 7. The long arm 86 of the bell cranklever is connected to the lower end of an elongated upright link 87 theupper end of which is pivotally connected to an anchor bracket '88provided on a fixed support. The other end of the cross shaft 85 carriesa lever 86 at the other side of the frame '7 similar to the long arm 86of the bell crank lever 84 and connected to an upright link 87' which issimilar to the link 87 and which ispivotally connectedat its upper endto an anchor bracket 88' provided on the fixed support at the other sideof 'the frame 7 from the anchor bracket 88. v V

The frame 7 is supp orted at its front end near the wall a 2 by a pivot89, and towards its outer end is supported gear in acasing 48, anupright shaft 49, a sprocket 50 on the shaft 49, a chain 51 and asprocket 52 on the lower.

end of the shaft 47. The sprocket 46 engages a chain 53 the two strandsof which extend parallel to the frame 7 and whichengages near the rearend of the frame 7 a sprocket 54 on the upper end of an upright shaft55.

One of the two strands of the chain 53 is attached to the carriage 24 ofthe nozzle tube rear support 8 and thereby when the motor is driven inthe appropriate direction the nozzle tube 1 may be advanced fromretracted to fully projected position and when the motor is reversedwithdrawn from fully projected to retracted position. The return strandof the chain engages teeth of a sprocket 61 on a spindle 62 journalledin the support 8 and carry ing a bevel wheel 63;.the bevel'wheel 63meshes witha V V bevel wheel 64 secured to the inner member 28of thesaid When the motor is driven so that one chain strand moves the support8 for longitudinal movement of the nozzletube, the return chain strand,passing the support 8 in the reverse direction .andengaging by its linksteeth of the sprocket 61, rotates the sprocket and by consequence alsothe nozzle tube 1. Means (not shown) are provided for ensuring contactof the return chain strand with teeth of the sprocket 61. I

The two strands of the chain S3extend close to' the carriage 34 of thefeed tube intermediate support 33 and meanstnot shown) in the'form ofa'traction device on the chain are provided so that when the'chain movesthe:

support 8 and the nozzle 1 fromthe retracted position .towards'the fullyprojected'position, then after a certain distance has been covered thetraction device catches the carriage 34 and advances it to ensure thattoo great a length of feed tube shall not be unsupported. Similarly,

from the two anchor brackets 88 and 88 through the said links 87; and87? and the arm 86 and lever 86' under the control of the arm 83 :of thebell crank lever 84, link 82 and shaft 73. Thus if the bellcrank lever84 is turned through an angle byacting upon'the short arm 83 thereofthrough the link 82,the arm 86 and lever 86' turn in unison through thesame angle, the upright links 87 and 87 turn in unison throughanlappropriate angle and the frame 7 asumes a different angular positionabout the pivot 89.

In. the operation of the soot blower, assuming that the nozzle tube 1 isin the retracted position shown, the electric motor 45 is started in theappropriate direction for the projection of the nozzle tube and bydriving the sprocket 46 near the front of the frame7 drives the chain 53around the said sprocket and around the sprocket 54 ne'arthe rear of theframe 7. The nozzle tube rear support 8, attached to a strand of thechain, advances and 'theifront end 3 of the nozzle tube provided withthe steam discharge apertures 4 is projected from the interior of thewall box 4 and into the space between tube banks of the tubulous fluidheater to be cleaned. The steam valve 43. iswopened when-the steamdischarge apertures 4 are clear of the wall 2 and steam travels alongthe steam feed tube 31 to the interior of the nozzle nozzle tube. axis.

tube 1 and thence is discharged through the apertures 4 in twodiametrically opposite jets at right angles to the The return strand ofthe chain 53 engaging the sprocketl 'on the nozzle tube rear support 3rotates'the .said sprocket as'the nozzle tube is advanced and .throughthecon'sequent rotation of, the support inner member 28 the nozzle tube1 is rotated as it is advanced.

/ Asthe chain 53 advances the nozzle tube it rotates the shaft 55 ofthesprocket 54at the rearfofthe frame 7;

during the reverse movement of the support 8' and the;

nozzle tube 1; from the fully projected to the'retracted position; thecarriage 11015 the nozzletube intermediate the rotation of the saidshaft effectsQ-through the sprocket 64, chain 65, sprocket 66, shaft 67and beveliwheels 68 and 70, rotation of the'nu t '71 on'thejthreadedpantof the shaft .73. The shaft 73 moves longitudinally and through the link82 and the arm 83'eflectsrotation' of the arm 86 support 19, which hasbeen carried forwardlybyvthe con- 7 tact therewith of the. carriage 24of the nozzleftube rear support 8, is, by means (not shown) in the formof afurth er traction device on the chain,-caught by the furthertraction device after a certain distance has been covered in, thewithdrawing directionrby the support 8 and the nozzle tube, jandalsomoved in the withdrawing direction and the lever 86 in the direction torock theframe 7 in a downward direction about the pivot 89. As, thenozzle tube 1 advancesmore and more the length of the unsupported partthereof beyond the nozzle, tube front; support bends'more and. moreunderjits own weight; at the ysarne time, the rear end of the frame 7 isincreasingly lowered with frespect to its front end so that the nozzletube forward end 3 is more and more raised in opposition to theincreasing sag of said front end, with the result that the nozzle tubefront end moves only a relatively short distance from a horizontal planerepresenting the ideal level at which the steam should be dischargedthrough the apertures 4 throughout the movement of the nozzle tube.

When the nozzle tube has reached its fully projected position theelectric motor 45 is reversed and the described longitudinal and rotarymovements of the nozzle tube and the rocking of frame 7 about the pivot89 are repeated in the reverse senses. During the nozzle tubewithdrawal, as the sag of the nozzle tube forward end becomes ever lessthe raising of the rear end of the frame 7 with respect to its pivot 89effects maintenance of the nozzle tube forward end near the horizontalplane mentioned. Shortly before the apertures 4 come level with the wall2 the steam valve 43 is closed.

The feed tube 31 is supported with respect to the frame 7 by the bracket32 and the supports 33 and 8, as already described, and outside the wall2 the nozzle tube 1 is supported with respect to the frame 7 by thesupports 8, and 6, as already described.

The bevel wheel 63 within the nozzletube rear support 8 is preferablyconnected to the inner member 28 with a degree of lost motion so thatthe helices of steam discharge from the nozzle tube during thewithdrawal of the nozzle tube do not coincide withthose during theprojection of the nozzle tube.

Referring to FIGURES 6 and 7, FIGURE 6 shows schematically the nozzletube 1 in retracted position sup- I ported on the frame 7 which ishorizontal, and FIGURE 7 shows the nozzle tube in fully projectedposition, its unsupported length bent under its own weight, and alsoshows the frame 7 in downwardly rocked positioned about the pivot 89 sothat the length of the nozzle tube supported by and extending from theframe 7 is rocked upwardly so as to oifset the sag of the nozzle tubeforward end. The nozzle tube forward end sags a distance indicated by101, but it is not positioned this distance below the horizontal plane102 from which the steam discharges are ideally required but by virtueof the compensatory tilting of the frame 7 is positioned on or close tosaid plane. It is positioned on or close to said plane also during theadvancing and withdrawing movements of the nozzle tube. As a result, thenozzle tube forward end 3 neither approaches too near to nor recedes toofar from the tube bank 103 above the soot blower or the tube bank 104below the soot blower.

In a modification, not illustrated, of the arrangement of FIGURES 1 to7, the frame 7, pivoted at its front end, is suspended adjacent its rearend not by the arm 86 and lever 36' and the upright suspension links 87and 87' respectively connected thereto but by a wire rope which is takenaround pulleys or a stationary set and pulleys of a second set mountedon top of the frame 7. One end of the wire rope is secured to a bracketon the frame 7 in which the second pulley set is accommodated, the wirerope is then taken alternately upwardly to the stationary pulley set anddownwardly to the second pulley set so that a speed-reducing hoist isformed and it is then taken around a guide pulley of horizontal axismounted on the frame from which it runsforwardly to itsqfront end whichis secured to the return strand of the chain 53; with this arrangement,as the nozzle tube 1 is advanced the frame 7 is rocked downwardly aboutits pivot 89 and as the nozzle tube is withdrawn the frame is rockedupwardly about the pivot; the speed ratio of the device is chosen sothat the front end 3 of the nozzle tube remains near the horizontalplane 102 between the upper and lower tube banks of the heat exchangerto be cleaned.

The means for suspending the frame 7 at its rear end may be arranged sothat when the nozzle tube is in the retracted position the nozzle tubeis inclined downwardly towards its front end ata small angle to thehorizontal.

Such inclination has the advantage that if the steam valve leaks theensuing condensate drains away through the apertures 4.

In the initial movement of projection of the forward end of such anozzle tube inclined downwardly when in the retracted position the saidforward end, moves slightly downwardly but the maximum lowering thereofis limited by the automatic rocking of the frame 7 as the nozzle tubeadvances. If, as when the speed-reducing hoist mentioned is used as thesuspension means, the ratio of rate of rock of the frame to rate ofreciprocation or longitudinal movement of the nozzle tube is constant,it may be arranged that the forward end of a nozzle tube inclineddownwardly in retracted position is, during the advance thereof, atfirst a short distance below, then a short dis tance above and finally ashort distance below a horizontal plane, and a very close approximationto movement of the forward end in a horizontal plane may be achieved.

I claim:

1. A fluid heater cleaner having an elongated nozzle tube axiallyreciprocable to advance the nozzle tube, for operation in a gas passageor the like containing a fluid heater to be cleaned, from aninoperative; retracted position and to withdraw the nozzle tube to theretracted position, wherein means are arranged automatically, throughoutthe advance of the nozzle tube, to increasingly rock about a horizontalaxis transverse to the nozzle tube the length of the nozzle tube outsidethe gas passage or the like in a manner tending to compensate increasingsag under gravity of the discharge end of the nozzle tube due to theincreasing unsupported length of the nozzle tube within the gas passageor the like and automatically, throughout the retraction of the nozzletube, to decreasingly rock about the said horizontal axis of the lengthof the nozzle tube outside the gas passage or the like in a mannertending to compensate decreasing sag under gravity of the discharge endof the nozzle tube due to the decreasing unsupported length of thenozzle tube within the gas passage or the like.

2. A fluid heater cleaner having an elongated nozzle tube axiallyreciprocable to advance the nozzle tube, for operation in a gas passageor the like containing a fluid heater to be cleaned, from aninoperative, retracted position and to withdraw the nozzle tube to theretracted position, comprising in combination a' carriage to which thenozzle tube is connected, a longitudinally extending track member whichis arranged outside the gas passage or the like and on which thecarriage is longitudinally movable and by which the carriage is guided,means mounted on the track member for supporting the nozzle tube foraxial reciprocation of the nozzle tube longitudinally of the trackmember, driving means for effecting reciprocation of the carriage alongthe track member and thereby axial reciprocation of the nozzle tube,supporting pivot means for the track member enabling rocking of thetrack member about a horizontal axis, rocking means for rocking thetrack member about thepivot means through a range of angles to thehorizontal and means coupling the driving means and the rocking meansand effective to rock the track member during advance of the nozzle tubein a manner tending to compensate sagging of the discharge end of thenozzle tube under the force of gravity acting on the said tube. a

3. A fluid heater cleaner having an elongated nozzle tube axiallyreciprocable to advance the nozzle tube axially reciprocable to advancethe nozzle tube, for operation in a gas passage or the like containing afluid heater which is arranged outside the gas passage or the like andon which the carriage is longitudinally movable and by which thecarriage is guided, means mounted on the track member for supporting thenozzle tube for axial reciprosupport, a lever pivotally mounted on thetrack member and linked to the 'fiXed support, means for turning thelever and thereby rocking the trackmember about the pivot means througha range of angles to the horizontal and means coupling the driving meansand the means for turning the said lever and effective to rock the trackmember during advance of the nozzle tube'in a manner tending tocompensate saggingof the discharge end of the nozzle tube under theforce of gravity acting on the said tube.

4. A fluid heater cleaner as claimed in claim 3, in which the means forturning the said lever comprise a threaded shaft linked to the lever anda rotatable nut engaging the threaded shaft and prevented fromaxial'moveme'nt, the driving means for the carriage includes a chainextending longitudinally of the track member and to which the carriageis attached and the coupling means are arranged to effect turning of thenut in accordance with longitudinal movement of the chain. a

5. A fluid heater cleaner as claimed in'claim 4, in which thechain is anendless chain, a sprocket on a driving shaft engages the chain adjacent,the end of the track member nearer the gaspassage or the like, a secondsprocket on a shaft engages the chain adjacent the other end of thetrack member and means are provided for turningthe nut in accordancewith the turning shaft of the second sprocket.

6. A fluid'heater cleaner as claimed in claim 2, in which the meanscoupling the driving means and the rocking means are arranged to ensurean inclination of the nozzle tube downwardly towards its discharge endwhen it is in its retracted position.

of the References Cited by the Examiner UNETED STATES PATENTS 2,722,03311/55 Glinn et al. 1s 317 2,897,532 8/59 (lantieri; 15-317 WALTERAl-scnaanrrimar Examiner.

' CHARLES A. WTILLMUTH, Examiner.

1. A FLUID HEATER CLEANER HAVING AN ELONGATED NOZZLE TUBE AXIALLYRECIPROCABLE TO ADVANCE THE NOZZLE TUBE, FOR OPERATION IN A GAS PASSAGEOR THE LIKE CONTAINING A FLUID HEATER TO BE CLEANED, FROM ANINOPERATIVE, RETRACTED POSITION AND TO WITHDRAW THE NOZZLE TUBE TO THERETRACTED POSITION, WHEREIN MEANS ARE ARRANGED AUTOMATICALLY, THROUGHOUTTHE ADVANCE OF THE NOZZLE TUBE, TO INCREASINGLY ROCK ABOUT A HORIZONTALAXIS TRANSVERSE TO THE NOZZLE TUBE THE LENGTH OF THE NOZZLE TUBE OUTSIDETHE GAS PASSAGE OR THE LIKE IN A MANNER TENDING TO COMPENSATE INCREASINGSAG UNDER GRAVITY OF THE DISCHARGE END OF THE NOZZLE TUBE DUE TO THEINCREASING UNSUPPORTED LENGTH OF THE NOZZLE TUBE WITHIN THE GAS PASSAGEOR THE LIKE AND AUTOMATICALLY, THROUGHOUT THE RETRACTION OF THE NOZZLETUBE, TO DECREASINGLY ROCK ABOUT THE SAID HORIZONTAL AXIS OF THE LENGTHOF THE NOZZLE TUBE OUTSIDE THE GAS PASSAGE OR THE LIKE IN A MANNERTENDING TO COMPENSATE DECREASING SAG UNDER GRAVITY OF THE DISCHARGE ENDOF THE NOZZLE TUBE DUE TO THE DECREASING UNSUPPORTED LENGTH OF THENOZZLE TUBE WITHIN THE GAS PASSAGE OR THE LIKE.